Nicotine insecticide and method of making the same



Patented Dec. 24, 1940 c s'rAras imir NKCOTINE INSECTICIDE AND METHOD OF:I GTHE SAME Ray Riley, Long Hsland'City, N. Y.. 'assignor to ThePermutit Company, New York, N. Y., a corporation at Delaware No Drawing.Application April 5, 1938, Serial 7 Claims. (or. 260-291) This inventionor discovery relates to nicotine insecticides and methods of making thesame; and it comprises as an insecticide adapted 'for even applicationto plant leaves in readily visible form, as a dry powder or as a liquidspray, an insoluble black, carbonaceous ion-exchanging preparation infine puiverulent form, characterized by carrying as the exchangeablepart there-. of, in fixed and insoluble form, a definite and wsubstantial proportion of nicotine and by being denser than water,easily wetted and readily dispersible in water, resistant to heat andmoisture, and of high nicotine concentration per unit volume and henceof high toxicity; and it further comprises a method of making such aninsecticide including the steps of treating a black pulverulentcarbonaceous ion-exchanging material -having exchangeable ions with'anaqueous solution of a nicotine salt until the preparation takes 20. up adefinite and large proportion of the nicotine ion and drying andpulverizing the thus treated preparation; all as more fully hereinafterset forth and as claimed.

Nicotine is a liquid alkaloid of high toxicity.

It. is volatile and has a relatively high vapor tension as a free base,rapidly evaporating in air. It occurs in tobacco, and is extractedtherefrom by various methods, for use as a basis for insecticidalpreparations, such as cattle dips.

- sprays for agricultural use, etc. Attempts have been made to devisedry nicotine preparations suitable for use as dusting powders, it oftenbeing more convenient and effective in practice to apply an insecticideas a powder than as aliquid. 85 Liquid nicotine is taken up to a certainextent by various absorbent and adsorbent materials such as bentonite,certain clays. peat. et but it is not fixedly held in definite quantityin a. form resistant to weather; in a form resisting ea evaporation andsolution. Most of the prior attempts to make nicotine powders have beenalong the lines of taking up nicotine on such materials in powderedform. It is unfortunately impossible to get any great percentage ofnicotine in such materials, at least in a stable and efiectivepermanently retained form. While these nicotine powders have a certaineffectiveness when fresh, they are not completely success- 56 ful evenwhen applied in large quantities and rapidly lose efliciency. An insecteating a leaf ordinarily takes in only a minute amount of adheringmatter and unless the concentration of nicotine in this adhering matteris sumciently w large, the insect may not be killed. Moreover,

zeolite-like materials, originally devised for use various ways, forexample, by treating lignite, coal, etc., with sulfuric acid underconditions and 2,206,007. Such materials are sometimes made by sulfatinglignite, coal, wood or other on such materials; zinc chloride forexample.

bentonite, clay, etc., dusts do not remain very effectively on the leafunder the drastic weather conditions, heat, wind, rain and leaf frictionwhich obtain in trees and other vegetation. In

. dusting a leaf with an insecticidal powder, the c way-in which thedust particle sticks to the leaf is quite as important as any otherfactor.

According to the present invention there is provided an improvedpulverulent nicotine insecticide, capable of being applied to plants, 10either in'liquid suspension as a spray, or as a dusting powder; Ineither case it clings and remains in plainly visible form. Uniformity ofdistribution can be followed by the eye. It is definite in composition,and has desirable mechanical properties as regards resistance tomoisture and heat, and adherence to the leaf.

It is easily wetted by water, and therefore readilyincorporated insprays. The same characteristic increases its efficacy as aninsecticide. 20

And even more important, it is of an exception-v ally high permanenttoxicity per unit volume, which means that a very small quantity issufficient to kill an insect which eats it. The effective toxicity ofinsecticides which are to be 25 eaten by insects goes up very rapidlywith increase in poison concentration per unit volume.

The invention depends in large degree on the recent developments ofcertain carbonaceous in water treatment, and having certain propertieslike those of the .inorganic alumina-silicate zeolites fo'rmerly known,and other additional properties. Commercially these substances are knownas carbonaceous zeolites and are on the 8 market as hard, rigid blackgranules of a size adapting them for use in a pervious bed watersoftener. These new substances are made in producinghighly insolublegranules of marked base exchange and ion exchange propertiesin general.Types of these new zeolites are tiescribed in United Statespatents,'Nos. 2,205,635

carbonizable material, and are sometimes made by the action of powerfuldehydrating agents These have many of the properties of ordinarysynthetic mineral zeolites, such as ability to extract bases from waterand to be regenerated with brine in repeated cycles, and they haveadditional properties, such as high acid resistance 55 which allows themto be regenerated with acids,

even with strong mineral acids.

cling to a leaf in easily visible form a substance of this type, usuallyin granular form, is first put in an acid condition by treatment withsome mineral acid so as to give it the power of taking "the zeolite.

nicotine can be taken up easily. Proportions of up cations. or it istreated with brine or other salt solution containing an exchangeablebase. The zeolite is then treated with an aqueous solution of a nicotinesalt. Treatment is carried on to the point where the zeolite becomes saturated with'chemically fixed nicotine. These carbon-zeolites have aselective action enabling themi to abstract nicotine preferentially fromimpure aqueous solutions such as those obtained by steeping tobaccowaste in. water or acid.

Such solutions can be used as the source of nicotine. Ontreating thezeolite granules with a nicotine sulfate solution, thegranules take upnicotine base to a certain, quite definite amount, depending mostly onthe exchange capacity of An extraordinarily large weight of 11 per centor more nicotine by weight in the dried material are readily obtained.The material, after steeping in the nicotine solution, is dried, eitherwith or without washing, at room temperature or in an oven. The driedmaterial is then pulverized, an operation readily performed. The powderis a black, highly toxic preparation of the advantages described.Because of the deep black color of the powder it is easy to obtain. aneven distribution of very small quantities on the leaf.. The process issimple and economical. Treatment of the zeolite with the various liquidsis by simple percolation. No soluble nicotine prod ucts appear to beformed. That is, upon percolating a nicotine solution through thezeolites, all the nicotine is taken up and fixedly held,

- until the point of saturation is reached; and the nicotine is held inhighly insoluble form. Using a salt of nicotine, such as sulfate, and acarbonaceous zeolite holding sodium as a cation the action is one ofbase exchange, analogous to the .sodium-calcium exchange in ordinaryzeolite water softening, in that the nicotine is taken up in definiteamount and fixed in insoluble condition, just as calcium is taken up insoftenin water. In the event that the carbon zeolite is preliminarilytreated with acid and is then charged with a solution containing anicotine salt, the action is analogous to that in removing bases fromwater with the aid of carbon zeolites.

In an example of a specific embodiment of a process within the purviewof the present invention,-a batch of 20 kilograms of 'a carbonaceouszeolite, of granule size 10-40 mesh, was 'im-.

sulfuric acid solution, containing some excess -nicotine. The materialwas then washed, and dried in air-andpulverized to finer than 200 or 300mesh; a fineness appropriate for use as a dustingpowder.

Set forth below are data on the nicotine content of the preparation,from measurements Weight of nicotine Apparent density Same as in Example1.

made on samples of the nicotine-charged granules after pulverization:

Average nicotine content (as free base) per cent by weight" 11.4 Averageweight of 100':c. of a bed of the 10-40 mesh material, in wet conditinngrams Weight of nicotine per 100 cc. of the preparation do 6.3

While the apparent density of the wet grandensity of more than 1 gramper cc.

(2) In another example,'a batch of 22 kgm.

of a 10-40 mesh carbonaceous zeolite was treated.

with normal HCl in excess, to insure complete conversion to the acidcondition. The material was washed and was disposed in the form of a bedin a suitable container and 2100 liters of 0.015 N nicotine sulfatesolution (5.1 kgm. of nicotine) were percolated therethrough at a flowrate of 10 liters per minute, at room temperature. About 1400 liters ofthe solution passed through before nicotine began to appear in theeffluent from the bed, in any substantial quantity (i. c. more than 10parts per million). .The nicotine-charged granules were then dried inair at room temperature, andwere ground to a fine powder.

Following are data on the product:

Per cent nicotine by weight (various samples) per 100 cc. material 6.8grams.

(3) In a third example, the carbonaceous zeolite was initially steepedin an excess of a nor-' 'mal. NaCl solution (weak brine) in lieu of a.

11.5% 14.8 (average 12.4). i

normal HCl solution, the rest of the process being carried out as inExample 2. The average nicotine content was about the same as in Ex--ample 2.

In all the cases the nicotine contents were determined by the U. S.Oificial Method: Assoc. Qflicial Agr. Chem., Methods ofAnalySis, thirdedition, 1930.

(4) Tobacco was steeped in water to obtain a solution containingnicotine in dilution about 0.0075 N. The solution also containedothersolubles incidentally leached from the tobacco. An acid washed granularcarbonaceous zeolite was treated with this solution to saturation, at C.The granules were washed, dried and pulverized. The dried granulescontained about '7 per cent nicotine by weight, or about 3.5 gramsnicotine in 100 cc. of the preparation; and about an equal weight ofother substances taken up from the tobacco ste'epings.

While in most cases the granules are washed prior to drying andpulverization, this step can be omitted if desired. a The preparationsare, usually made to contain nicotine in proportions corresponding to atleast 3 grams nicotine in 100 cc.

These carbonaceous zeolites have a definite capacity for nicotine,corresponding to the ultimate exchange capacity of the zeolite asmeasured for Na, Ca, etc., and standardized insecticide preparations ofvarious desired potencies can be manufactured, within close limits. The

process readily lends itself to large scale commercial operation. Thezeolite granules, being denser than water, can be treated with thevarious liquids by percolation, which is probably the best and simplestpossible method of charging the granules with the nicotine. The granulescan be readily pulverized to fine powders of desirable character.

The new preparation is, as stated, remarkably stable to heat andmoisture. .Upon heating a sample of the preparation for three hours at100 C. there was negligible loss of nicotine, which indicates that thenicotine is fixed in highly nonvolatile form. In a test showing theremarkable non-volatility and insolubility oi the nicotine content ofthe preparation, a sample of the preparation containing 11.5 per centnicotine was maintained 8 hours at a temperature of -60 0., and thenimmersed in water for 16 hours; the alternating treatments beingcontinued for 10 days. At the end of this'time, the nicotine content wasstill 9.3 per cent, the loss being some 20 per cent. The conditionsobtaining in. this test are of course much more drastic than would occurin any normal utilization of the product for its intended purposes.

The high insolubility and non-volatility of the nicotine preparationmake for markedly greater safety in handling and use than with priorpreparations.

What I claim is:

1. An insecticide comprising finely divided insoluble carbonaceousion-exchange material prepared by reacting carbonizable material with aconcentrated dehydrating agent and carrying of a mass of wet particles.

2. An insecticide comprising finely divided insoluble black carbonaceousion-exchange material prepared by reacting carbonizable material with aconcentrated dehydrating agent are carrying nicotine in insoluble,exchangeable form, the amount of nicotine corresponding to at leastabout 7 per cent by Weight and to the proportion of 3 grams per cc. of amass of wet particles.

3. An insecticide comprising an insoluble black synthetic carbonaceousion-exchange product as a finely divided preparation denser than water,stable to heat and moisture and carrying nicotine in the exchangeablepart thereof in insoluble form; the carbonaceous product being thereaction product of carbonaceous material and a concentrated powerfuldehydrating agent at elevated temperatures.

4. An insecticide comprising an insoluble solid, black sulfatedcarbonaceous. material of ion-exchanging character, carrying nicotlne inthe exchangeable part thereof in insoluble form, the nicotine contentbeing stable and substantially non-volatile under the action of heat andmoisture.

5. An insecticide comprising an insoluble solid black synthetic sulfatedcarbonaceous material having a high capacity for ion-exchange carryingexchangeable nicotine and characterized by carrying the nicotine in suchform as to resist loss by volatilization when heated.

6. The insecticide of claim 5 wherein the proportion of nicotinecorresponds to at least about 3 grams per 100 cc. of the preparation.

7. A method of making an insecticide which comprises passing an aqueousextract of tobacco through a bed of an insoluble solid, synthetic.sulfated carbonaceous substance having a high capacity for ion exchangeand containing exchangeable ions until a definite quantity of nicotineis taken up by the substance in insoluble form in exchange for the ionstherein,.drying the nicotine-charged substance and pulverizing it.

CERTIFICATE OF CORRECTION. Patent No. 2, 226,589. 7 December 214,191.;0.

' RAY RILEY.

It 1s hereby certified that error appears in the printed specification.

of the above numbered patent requiring correction follows: Page 3 secondcolumn, line 5, claim 2, for the word "are" read --e.nd--; and thet the'seid Letters Patent should be read with this correction therein'that thesame may conform to the'record of the case in the ietent Office,

Signed and seeled this 11m day of February, A'. D. 19141.

Henry Ven Arsdale, Acting commissioner of Patents.

